What is the recommended treatment for a patient presenting with diarrhoea, considering their unique medical history and potential complicating factors?

Treatment of Diarrhoea

The cornerstone of diarrhoea management is aggressive rehydration with oral rehydration solutions for mild-moderate cases and intravenous fluids for severe dehydration, combined with loperamide for uncomplicated cases, while complicated presentations require hospitalization with IV fluids, octreotide, and empiric antibiotics. 1, 2

Initial Classification and Risk Stratification

Immediately classify the diarrhoea as uncomplicated versus complicated to determine the treatment pathway 1, 2:

Uncomplicated Diarrhoea (Outpatient Management)

• Grade 1-2 diarrhoea without warning signs 1
• No fever, severe cramping, vomiting, or diminished performance status 1
• No signs of dehydration (normal blood pressure, adequate skin turgor, moist mucous membranes) 2

Complicated Diarrhoea (Requires Hospitalization)

• Any of the following mandate admission: sepsis, neutropaenia, bleeding, severe dehydration, grade 3-4 diarrhoea 1
• Moderate to severe cramping, persistent vomiting, fever, or diminished performance status 1, 2
• Orthostatic hypotension, altered mental status, or weakness 2

Rehydration Strategy (The Most Critical Intervention)

For Mild Diarrhoea (Uncomplicated)

• Start oral rehydration therapy immediately with WHO oral rehydration solution containing 65-70 mEq/L sodium and 75-90 mmol/L glucose 1
• Prescribe 2200-4000 mL/day of ORS, adjusting based on ongoing losses 1
• Diluted fruit juices, broths, and saltine crackers are acceptable alternatives for very mild cases 1
• In elderly patients and all grade 2 diarrhoea, ORS is mandatory (not optional) due to higher risk of complications 1

For Severe Dehydration or Grade 3-4 Diarrhoea

• Initiate intravenous rehydration with isotonic saline or balanced salt solution 1
• If tachycardic or potentially septic, give initial fluid bolus of 20 mL/kg 1
• Continue rapid fluid replacement until clinical signs improve (normalized blood pressure, urine output, mental status) 1
• Target urine output >0.5 mL/kg/h and adequate central venous pressure 1
• Fluid administration rate must exceed ongoing losses: urine output + 30-50 mL/h insensible losses + gastrointestinal losses 1
• Caution: Avoid overhydration in elderly patients with heart or kidney failure 1

Pharmacological Management

Uncomplicated Diarrhoea

Loperamide is first-line antidiarrhoeal therapy 1, 2:

• Initial dose: 4 mg, then 2 mg every 4 hours or after each unformed stool 1
• Maximum daily dose: 16 mg 1
• Alternative opioids (codeine, morphine, tincture of opium) can be used if loperamide fails 1

Complicated Diarrhoea Requiring Hospitalization

Implement intensive management protocol 1:

1. Octreotide: Start 100-150 mcg subcutaneous or IV three times daily 1

   • If severely dehydrated, use IV infusion at 25-50 mcg/h 1
   • Escalate up to 500 mcg subcutaneous three times daily until diarrhoea controlled 1

2. Empiric antibiotics (fluoroquinolone) for complicated cases 1

   • Obtain stool work-up for blood, C. difficile, Salmonella, E. coli, Campylobacter 1
   • Check complete blood count and electrolyte profile 1

Special Case: Neutropaenic Enterocolitis (High Mortality Risk)

This is a medical emergency requiring aggressive intervention 1:

• Broad-spectrum antibiotics covering gram-negatives, gram-positives, and anaerobes 1
• Reasonable choices: piperacillin-tazobactam OR imipenem-cilastatin monotherapy 1
• Alternative: cefepime or ceftazidime PLUS metronidazole 1
• Add amphotericin if no response to antibacterials (fungaemia is common) 1
• Granulocyte colony-stimulating factors (G-CSF) 1
• Nasogastric decompression, bowel rest, serial abdominal exams 1
• AVOID anticholinergics, antidiarrhoeals, and opioids (may aggravate ileus) 1
• Blood transfusions often necessary for bloody diarrhoea 1

Surgical intervention indications (controversial but potentially life-saving) 1:

• Persistent GI bleeding despite correction of coagulopathy
• Free intraperitoneal perforation
• Abscess formation
• Clinical deterioration despite aggressive medical management
• If surgery performed: right hemicolectomy with ileostomy and mucous fistula (avoid primary anastomosis due to high leak risk) 1

Dietary Modifications

• Eliminate lactose-containing products (except yogurt and firm cheeses) during active diarrhoea 1
• Avoid coffee, alcohol, and spices 1
• Reduce insoluble fiber intake 1
• Maintain glucose-containing drinks and electrolyte-rich soups 2

Critical Monitoring Parameters

• Reassess hydration status frequently to ensure dehydration is not worsening 1
• Monitor for oliguric acute kidney injury (<0.5 mL/kg/h despite adequate CVP) - requires urgent nephrology consultation 1
• Record stool frequency and characteristics 2
• In incontinent patients, use skin barriers to prevent pressure ulcers 1

Common Pitfalls to Avoid

• Never neglect rehydration while focusing solely on antimotility agents - dehydration kills, not the diarrhoea itself 2
• Do not use antimicrobials routinely for acute watery diarrhoea without appropriate indications 2
• Always exclude fecal impaction with overflow diarrhoea in elderly patients presenting with alternating constipation and diarrhoea 1, 2
• Avoid rapid fluid resuscitation in mild-moderate hypovolaemia - match rate to ongoing losses 1
• If diarrhoea persists beyond 48 hours despite treatment, investigate further with stool studies 2